1. Field of the Invention
The invention pertains to a surface mounted signal device for elevators having a base plate with a detachable connection with a housing wherein the base plate has turned up ends that are rearwardly retained, relative to the housing, by retaining means.
2. Discussion of the Background of the Invention and Material Information
European Patent Publication EP-A1 0 524 428 discloses an indicator device of the flat type for elevators wherein a base plate is assembled, with its turned up small ends and attachment screws, to a wall. On the lower small side of a housing, that is open toward the wall, bolts are arranged which serve to connect the lower turned up end of the base plate with the housing. On the upper small side of the housing, adjusting screws serve to connect the upper turned up end of the base plate with the housing. The front side of the housing has an opening for receiving a filter plate. On the front inner side of the housing, near the opening, threaded bolts serve to retain a lens carrier, via clips, with the lens carrier being pressed frontally against the filter plate by means of screw nuts. The rear side is closed by an actuatable or pressable circuit, located on the lens carrier. An insulating plate, arranged on the base plate, protects the pressable circuit against short circuits.
A disadvantage of this known construction is that, with differing indicating devices of the same type, only the base plate is the same in terms of size and shape. Depending upon the lens shape and lens size, housings with differing frontal openings are required.